ES2792908T3 - Rescue apparatus and lift - Google Patents

Abstract

A rescue apparatus for an elevator, the rescue apparatus comprising: a brake control unit (1) having input terminals (2A, 2B) for connection to a power supply (3A, 3B), output terminals ( 4) for connection to a magnetizing coil (6) of an electromagnetic brake (7), and two independently controllable brake release switches (8A, 8B; 9A, 9B) each associated with at least one of the input terminals ( 2A, 2B) and adapted, in the open state, to prevent the supply of current from the power supply (3A, 3B) to the magnetizing coil (6) and, in the closed state, to allow the supply of current from the power source. supply (3A, 3B) to the magnetizing coil (6); a control cable (10) comprising a plurality of control signal cables (11A, 11B, 11C); and a remote control panel (12) for operating the two brake release switches (8A, 8B; 9A, 9B), the remote control panel (12) being coupled via the control cable (10) to the unit control panel (1), the remote control panel (12) comprising two manually actuated switches (13A, 13B), one of the actuation switches (13A, 13B) being coupled through a first signal cable of control (11A, 11B) to a control post (8C, 9C) of the first brake release switch (8A, 8B); 9A, 9B) and the other of the actuation switches (13A, 13B) being coupled through a second control signal cable (11A, 11B) to a control post (8C, 9C) of the second opening switch of the brake (8A, 8B; 9A, 9B).

Description

DESCRIPTION

Rescue apparatus and lift

Field of the invention

The subject described here refers to elevator rescue apparatus, that is, apparatus for rescuing elevator passengers from an elevator car.

Background

Sometimes an operational anomaly, such as a power failure, can cause the elevator car to stop between landings, outside of the appropriate stop zone. One solution to remedy this situation is to manually open the hoisting machinery brakes using a manual brake release lever. The opening of the brakes of the machinery causes the movement of the elevator car towards the nearest landing by means of gravity.

The brake lever can be located, for example, in the elevator landing area, outside the elevator shaft. The brake lever is connected to the lifting machinery brakes through a brake release cable (mechanical cable) in such a way that the brake release cable mechanically opens the machinery brakes, when the lever is turned .

The technician holds the machinery brakes open by pulling the lever, visually observes the movement of the elevator car, and returns the lever to its initial position to stop the elevator car when it reaches the door area. When you are in the door area, the elevator car floor is at the same level as the landing floor, so that passengers can exit the elevator car onto the landing.

This type of brake release mechanism should be located not too far from the lifting machinery brakes; otherwise, the length of the brake release cable could cause problems. As the length of the brake release cable increases, the force required to turn the lever also increases. Dirt, corrosion, etc. they can easily block the movement of the very long brake release cable, thus complicating the brake release / rescue operation process.

On the other hand, it would sometimes be beneficial to arrange the manual brake release interface (eg brake lever) away from the lifting machinery brakes. For example, in some elevators it is desired to locate the manual brake release interface on the lowest landing, while the lifting machine / machinery brakes are located at the top of the elevator shaft.

A smooth rescue operation requires some experience in using the brake lever. Therefore, a device that is easier to use is needed, but with the same security without being compromised.

Document WO 2011/001197 A1 discloses a rescue apparatus for an elevator.

Object of the invention

In view of the above, the aim of this invention is to introduce an improved rescue apparatus for an elevator, which provides flexible positioning of the manual brake release interface (hereinafter referred to as "remote control unit") in relation to the brake or lifting equipment brakes. Therefore, the invention discloses a rescue apparatus according to claim 1. Some preferred embodiments of the invention are described in the dependent claims. Some embodiments of the invention, as well as combinations of various embodiments of the invention, are presented in the specification and drawings of the present application.

Summary of the invention

One aspect of the invention is a rescue apparatus for an elevator, the rescue apparatus comprising a brake control unit having input terminals for connecting to a power source, output terminals for connecting to a magnetizing coil of a brake electromagnetic and at least one controllable brake release switch associated with at least one of the input terminals and adapted, in a first switching state, to prevent the supply of current from the power source to the magnetizing coil and, in a second switching state, to allow current supply from the power source to the magnetizing coil. The rescue apparatus also comprises a control cable comprising one or more control signal cables and a remote control panel for operating at least one brake release switch, the remote control panel being coupled via the control cable to the brake control unit.

Another aspect of the invention is an elevator, comprising an elevator car and an elevator machine configured to drive the elevator car into the elevator shaft between the landings according to the service requests of the elevator passengers, the elevator machine including one or more electromagnetic brakes. The elevator comprises a rescue apparatus, according to the disclosure.

Another aspect of the invention is a modification kit comprising a rescue apparatus according to the disclosure, which is suitable to be installed in an elevator according to the disclosure.

The revealed rescue apparatus is simple in structure; therefore the operation of the rescue apparatus can be analyzed in detail to achieve a high level of safety. The rescue apparatus is also suitable for installation in various types of elevators, because the location of the remote control unit can be selected substantially freely in relation to the brake control unit, for example the length of the control cable It is not a limiting factor in the same way as traditional brake levers with mechanical brake release cables. In a preferred embodiment, the controllable brake release switch (s) of the brake control unit is / are safety relays. This type of relay has mechanical contacts with large isolation distances, which guarantees great reliability in the current cutting procedure of the magnetizing coil. Therefore, reliable operation of the lifting machinery brakes can also be achieved during the rescue operation.

According to the invention, the remote control panel comprises a manually operated actuation switch coupled via the control signal wire of the control wire to the control post of the brake release switch.

According to the invention, the brake control unit comprises two controllable brake release switches, which are adapted to prevent the supply of current to the magnetizing coil independently of each other, and the remote control panel comprises two switches manually operated actuators, one of which is coupled by a first control signal wire to a control pole of the first brake release switch and the other is coupled by a second control signal wire to a control pole of the second brake release switch. This means that the current from the magnetizing coil can be interrupted by two independent means (the brake release switches), controlled (with the actuation switches, via separate control signal cables) independent of each other. Therefore, if one of the brake release switches is for some reason stuck in the closed position, the other brake release switch continues to work and can apply the brake by interrupting the current from the magnetizing coil.

According to one embodiment, the brake control unit comprises a switching status indicator for indicating the switching status of the brake release switches.

According to one embodiment, the remote control panel comprises a manually operated mode selection switch connected in series with one or more actuation switches. This means that rescue operation with the actuation switch (s) is not possible until the mode selection switch has been placed in the rescue position.

According to one embodiment, the power source is a reserve power source. This means that rescue operation is possible also during a power outage, supplying current to the magnetizing coil (s) from the backup power supply.

According to one embodiment, the power source is a DC backup power source, and in that the main circuit comprises a DC / DC converter for supplying electricity from the backup power source to the magnetizing coil. This means that the DC / DC converter can be used to convert the low voltage from the DC backup power supply to a higher voltage for the magnetizing coil (s). In a preferred embodiment, the DC backup power source is a battery.

According to one embodiment, the power source is the electrical network. In a preferred embodiment, both the main and standby power supplies can be connected to the input terminals. In one embodiment, the control unit is configured such that power is supplied from the standby power source only in the event of a mains failure, and otherwise the power is supplied from the mains.

According to one embodiment, the brake control unit further comprises pass-through terminals for the output cables of a brake control device in normal mode, as well as a disconnect switch installed between the pass-through terminals and the output terminals. The control pole of the switch-disconnector is coupled via a control signal cable to the mode selection switch on the remote control panel, such that the switch-disconnector is operable to selectively disconnect or connect the feed-through terminals to the terminals. depending on the state of the mode selection switch. This means that the normal mode brake release device can be separated from the magnetizing coil current supply circuit in rescue mode by turning the mode selection switch in rescue mode. Therefore, rescue operation is still possible even if the brake release device in normal mode fails, for example if the output of the brake release switch in normal mode is short-circuited.

According to one embodiment, the disconnecting switch is a switch having first inputs coupled to the pass-through terminals, second inputs coupled to the rescue time current, and outputs coupled to the pass-through terminals. output terminals. This means that the brake control unit is separated from the normal brake release device also during normal elevator operation, when the mode selection switch is turned into normal mode. This reduces the probability of failure of the brake control unit.

According to one embodiment, the mode selection switch has a contact in the elevator safety chain. The mode selection switch safety chain contact is set to be in the open state when the mode selection switch is in rescue mode and to be in the closed state when the mode selection switch is in normal mode. This means that normal elevator operation can be prevented during the rescue operation by turning the mode select switch to rescue mode, which interrupts the elevator safety chain.

According to one embodiment, the rescue apparatus comprises controllable dynamic braking switches having terminals for coupling to a stator winding of a permanent magnet motor, the dynamic braking switches being adapted to generate, in the closed state, a braking current at from the electromotive force of the permanent magnet motor, in which the control pole or poles of the dynamic braking switches are coupled to the elevator safety chain, so that the dynamic braking switches are in the closed state when elevator security chain is interrupted. This means that dynamic braking can be activated from the remote control unit by turning the mode selection switch in rescue mode, thus interrupting the elevator safety chain. Therefore, the speed / acceleration of the elevator car during the rescue operation can also be reduced by dynamic braking, leading to longer open / close intervals for the brakes of the lifting machinery (for example, the The frequency of opening / closing the brakes can decrease without causing the activation of the safety equipment due to overspeeding, which means that the rescue operation is easier to perform).

According to one embodiment, the control cable comprises a power cable coupled to the backup power source, and the remote control unit comprises an indicator of the status of the backup power source. This means that the operating status of the backup power supply (eg battery) can be controlled from the remote control unit. This is especially useful in cases where the backup power supply is arranged in the elevator shaft and the remote control unit is arranged on the landing floor, outside the elevator shaft.

According to one embodiment, the brake control unit comprises a solid state switch associated with the output terminals to selectively prevent or allow the supply of electricity to the magnetizing coil. This means that the power supply to the magnetizing coil can be interrupted / resumed with the solid state switch as well. The use of the mechanical brake release switch (s) is only necessary in certain operating situations, for example when the actuation switch (s) on the remote control unit is released. If the mechanical brake release switch (s) are used only when necessary, and otherwise using the solid state switch, the number of switching events of the switch (s) The mechanical brake release (s) can be reduced and the service life of the brakes can be increased.

According to one embodiment, the brake control unit comprises a safety logic having an output coupled to the control pole of the solid state switch and an input coupled to the switch status indicator, for receiving information on the switching status of the switches brake release. The safety logic comprises a logic element configured to compare the switching states of the received brake open switches and to block the power supply to the output terminals in the event that one of the brake open switches remains in the closed state while that the other changes from the closed state to the open state and then back to the closed state. This means that the current supply to the magnetization is prevented by the solid state switch and therefore the brake does not open if both brake release switches are not opened between consecutive rescue operations (for example, when one brake release switch opens interrupting the current supply to the magnetizing coil, also the other has to open before the current supply to the magnetizing coil can be resumed). In this way, it is possible to detect if one of the brake release (mechanical) switches has failed and is stuck in the closed position. In this way the safety of the rescue apparatus can be increased.

According to one embodiment, the brake control unit comprises a modulator coupled to the control pole of the solid state switch. The modulator is configured to adjust the voltage of the output terminals by modulating the solid state switch. This means that it is possible to reduce the voltage at the output terminals / magnetizing current after the brake has been opened. When the brake has opened, a smaller magnetizing coil current is adequate to keep the brake open. Thus, by reducing the magnetizing current to a lower value, which is nevertheless suitable for keeping the brake open, the power losses of the magnetizing coil can be reduced and the rise in temperature of the brake coil decreased.

According to one embodiment, the brake control unit comprises a speed supervision logic having an input for receiving the movement data of the elevator car and an output coupled to the control pole of the solid state switch. This means that the brake can be controlled (open / closed) by responding to motion data by changing the current in the magnetizing coil through the solid state switch.

According to one embodiment, the speed supervision logic is configured

• to determine elevator car speed from motion data, and

• to compare the speed of the elevator car with a threshold value, and

• to interrupt the supply of electricity to the magnetizing coil if the speed of the elevator car exceeds the threshold value. This means that the brake can be applied to slow down the movement of the elevator car if the speed of the elevator car becomes too high.

According to one embodiment, the speed monitoring logic is coupled to the switching status indicator to receive information on the switching status of the brake open switches. This means that information from the switching state of the brake release switches is used, among other things, to determine when the lifting machinery brakes are released and a new rescue run is started. In one embodiment, the speed monitoring logic is configured to interrupt the supply of current to the magnetizing coil if the speed of the elevator car remains within a tolerance determined at zero for a predetermined period of time after the brake release switches have gone to the closed state. Closing of the brake release switches allows current to be supplied to the magnetizing coil, indicating the start of a new rescue run. When a new rescue run is started and the elevator car begins to move, the speed of the car must also change to a value other than zero; otherwise, if the measurement data still indicates that the car speed is zero, an error in the motion data (such as motion sensor failure) is judged and the brake is applied. In a preferred embodiment, the predetermined time period is 3 seconds, after which, if the car speed remains zero, the brake is applied and the elevator car stops. If this procedure is repeated, for example, the brake release switches are reopened and closed, the brake can be reopened for the same predetermined period of time. In this way, it is possible, by means of the remote control unit, to gradually move the elevator car to the door area despite the failure of the motion sensor.

According to one embodiment, the movement data of the elevator car is measurement data from an acceleration sensor mounted in the elevator car. This means that the movement of the elevator car can be measured directly from the elevator car.

According to one embodiment, the remote control unit is arranged on the landing. This means that a rescue operation can also be carried out from the landing, outside the elevator shaft.

According to one embodiment, the lifting machine, the normal mode brake controller, the brake control unit and the backup power supply are arranged in the gap, very close to each other. This means that only short power cables are needed between them, which simplifies electrification and reduces potential EMC disturbances.

Brief description of the drawings

The invention will now be described in more detail by means of some examples of its embodiments, which by themselves do not limit the scope of the invention, with reference to the attached drawings, in which

Figure 1 shows a diagram of an elevator according to one embodiment.

Figure 2 shows a circuit diagram of a rescue apparatus according to one embodiment.

Figure 3 shows the basic operating elements of an electromagnetic brake according to one embodiment.

Figure 4 shows an elevator drive according to one embodiment.

A more detailed description of the preferred embodiments of the invention

For the sake of intelligibility, only those features that are considered necessary to understand the invention are depicted in Figures 1 to 4. Therefore, for example, certain components / functions that are widely known to be present in the corresponding art may not be represented.

The description always uses the same references for the same elements.

Figure 1 is a schematic of an elevator according to an exemplary embodiment. The elevator comprises an elevator car 31 and an elevator drive. The components of the elevator drive are further shown in Figure 4. Therefore, the elevator drive includes a lifting machine 23 and a frequency converter 40. The lifting machine 23 is configured to drive the car 31 in the shaft of the elevator. elevator 33 between landings 34 in accordance with service requests from elevator passengers, as is known in the art.

The frequency converter 40 and the lift machine 23 are mounted near the upper end of the elevator shaft 33. The lift machine 23 includes a permanent magnet motor 22 and a rotating traction sheave (not shown), mounted on the shaft of the permanent magnet motor 22. The frequency converter 40 is connected to the stator 21 of the permanent magnet motor 22 to supply power to the permanent magnet motor 22. The elevator car 31 and the counterweight (not shown) are suspended with cable ties. elevation (not shown). The lifting haulk is operated by the lifting machine traction sheave 23. The permanent magnet motor 22 drives the traction sheave, which causes the elevator car 31 and the counterweight to move in opposite directions in the shaft. elevator 33.

Alternatively, the elevator machine 23 and the frequency converter 40 can be arranged in the pit of the elevator shaft. The lifting system can also have separate lifting and suspension hawsers. In this case, the lifting clamps can pass through the traction sheave of the lifting machine 23 which is located in the pit. In addition, the suspension cleat can be attached to at least one pulley near the upper end of the gap. The term "hawser" is understood to refer to both traditional circular ropes and straps. Alternatively, the lifting machine 23 and the frequency converter 40 can be arranged in a machine room separate from the shaft 33.

The elevator, according to the disclosure, can also be implemented without a counterweight.

The lifting machine 23 of figure 1 comprises two electromagnetic brakes 7 to slow down the movement of the traction sheave. One of the brakes 7 is shown in Figure 3. The electromagnetic brake 7 includes a stationary brake body 35, which is attached to the stationary body of the lifting machine 23, and an armature 36 arranged to move relative to the brake body. 35. A spring 37 is positioned between the brake body 35 and the armature 36 to apply a biasing force between them. An electromagnet with the magnetizing coil 6 is mounted inside the body of the brake 35. The brakes 7 are applied by driving the armature against the braking surface 38 of the rotating part of the lifting machine 23 by the biasing force of the spring 37. The brake 7 opens by exciting magnetizing coil 6. When energized, magnetizing coil 6 causes an attraction between brake body 35 and armature 36, attraction which in turn causes armature 36 to disengage from braking surface 38 by medium biasing force of spring 37.

A normal mode brake controller 17 is connected to the magnetizing coils 6 of the brakes 7 to selectively open or close the brakes 7 during normal elevator operation. The normal mode brake controller 17 is arranged in the frequency converter 40, very close to the lifting machine 23 and the brakes 7. In some alternative embodiments the normal mode brake controller 17 is arranged in a mounted control panel on the landing of the elevator 34. In the normal mode, the brakes 7 are released when starting a new elevator stroke, and the brakes 7 are applied at the end of the stroke to keep the elevator car 31 at rest. The brakes 7 are controlled to open by supplying the required amount of current to the magnetizing coils 6. The brakes 7 are applied interrupting the current supply.

In a non-conforming run of the elevator car 31 it can be stopped in such a way that the elevator car is stuck outside the landing 34, so that the passengers of the elevator 31 cannot leave the elevator car 31. A functional non-conformity can be caused, for example, by a power failure of the electrical network 3A, or by an operating error or failure of the elevator control system, for example. For this reason, the elevator of Fig. 1 has a rescue apparatus to perform a rescue operation in which a technician safely returns the stuck elevator car to a landing 34 so that passengers can exit the car 31. This happens by opening the brakes 7 to move the elevator car 31 by means of gravity.

The rescue apparatus comprises a brake control unit 1, a remote control unit 12 and a backup battery 3B. The brake control unit 1 and the backup battery 3B are located in the gap 33, very close to the lift machine 23 / brakes 7 and the brake controller in normal mode 17. The remote control unit 12 is arranged outside the elevator shaft 33, in a control panel 39 mounted on the door frame of the landing at the entrance to the pit. The remote control unit 12 is coupled to the brake control unit 1 through a control cable 10.

Figure 2 shows the circuit diagram of the rescue apparatus of figure 1. The brake control unit 1 has the input terminals 2A connected to the mains 3A, as well as the input terminals 2B connected to the backup battery 3B. The electrical network 3A can be, for example, a 230 V AC voltage network. The brake control unit 1 also has the output terminals 4 connected to the magnetizing coils 6 of the two electromagnetic brakes 7. The brake control unit 1 also has a solid state switch in the form of an IGBT transistor 25, which is associated with the output terminals 4 to prevent or selectively allow the supply of electricity to the magnetizing coils 6.

A DC / DC converter 16 is coupled between the input terminals 2B and the solid state switch 25. The DC / DC converter 16 supplies current from the backup battery 3B to the input of the IGBT transistor 25. At the same time, the converter DC / DC 16 also converts the voltage of battery 3B to a higher DC voltage value, necessary for the magnetizing coils 6. During normal elevator operation, battery 3B is charged with battery charger 43.

The brake control unit 1 comprises two controllable brake release switches 8A, 8B; 9A, 9B in the form of safety relays. Both relays have two safety contacts 8A, 8B; 9A, 9B. The safety contacts 8A, 8B; 9A, 9B are associated with the corresponding input terminals 2A, 2B. Each safety relay 8A, 8B; 9A, 9B is adapted to avoid supplying current to the corresponding magnetizing coil 6 independent of another safety relay. This means that if one of the safety relays 8A, 8B; 9A, 9B has one safety contact stuck in the closed position, the other 8A, 8B; 9A, 9B continues to work and can apply brake 7 by interrupting current from magnetizing coil 6.

The safety contacts 8A, 8B; 9A, 9B are normal open (N.O.) contacts. They are mounted in the main circuit of the brake control unit 1 in such a way that in the open state they prevent the supply of current to the magnetizing coils 6 and in the closed state they allow the supply of current to the magnetizing coils 6.

The control cable 10 comprises the control signal cables 11A, 11B, 11C. The control signals are sent from the remote control unit 12 to the brake control unit 1 through the control signal cables 11A, 11B, 11C, as revealed below.

The remote control unit 12 comprises two manually operated actuation switches 13A, 13B. One of the actuating switches 13B is coupled via a first control signal wire 11B to a control pole 8C of the first brake release switch 8A, 8B and the other is coupled via a second control signal wire 11A to a control pole 9C of the second brake release switch 9A, 9B.

The remote control unit 12 also comprises a manually operated mode selection switch, having a contact 15A connected in series with the actuation switches 13A, 13B. The mode selection switch 15 has two modes (positions), the normal mode (which allows the normal operation of the elevator) and the rescue mode (which allows the rescue operation). The contact of the mode selection switch 15A is in the closed state in the rescue mode and in the open state in the normal mode. When the contact of the mode selection switch 15A is closed, the actuating switches 13A, 13B receive the DC supply voltage VCC. The DC supply voltage VCC comes from the backup battery 3B through the control cable 11D.

When the contacts of the actuation switch 13A, 13B are closed manually (by operating the manual pushbuttons), the control voltage VCC is connected through the control cables 11A, 11B to the control coils 8C, 9C of the control relays. safety of the brake opening switch, causing the closure of safety contacts 8A, 8B; 9A, 9B. This has two effects: on the one hand, the current can flow from the network 3A to the IGBT transistor 25 through the safety contacts 8A, 9A and a rectifier bridge of diodes 41. At the same time, the closure of the safety contacts 8B, 9B connects the control voltages of the DC / DC converter 16, thus allowing the operation of the DC / DC converter.

The remote control unit 12 comprises a VCC voltage status indicator 24, which also indicates the status of the backup battery 3B. The indicator 24 can be, for example, an LED. By means of the indicator 24 it is possible to check the status of the backup battery 3B without entering the elevator shaft 33.

The remote control unit 12 also has an overspeed limiter switch 42. The overspeed limiter switch 42 is opened with a predetermined overspeed lever, causing the safety relay contacts 8A, 8B to open; 9a, 9B.

A modulator 27 is coupled to the control pole of the IGBT transistor 25. The modulator 27 turns the IGBT transistor 25 on and off with a high switching frequency according to a specific switching pattern to adjust the voltage of the output terminal 4. Therefore, the voltage of the output terminal 4 can be lowered to avoid excessive power losses in the magnetizing coils 6. On the other hand, the voltage of the output terminal 4 can be temporarily raised to ensure that the brakes of machinery 7 are open properly. The switching pattern depends on the modulation procedure used, as understood by an expert. Suitable modulation procedures that are known in the art are, for example, pulse width modulation, frequency modulation, and hysteresis modulation.

The brake control unit 1 comprises a switching status indicator 14 for indicating the switching status of the safety contacts 8A, 8B; 9A, 9B. The switching status indicator 14 includes the optocouplers 14A, 14B coupled to the safety contacts 8B, 9B.

The brake control unit 1 further comprises a safety logic 26. The safety logic 26 has an output coupled to the modulator 27 to selectively enable or disable the control signals to the control pole of the IGBT transistor 25. The logic inputs Safety switches 26 are coupled to the outputs of optocouplers 14A, 14B. Safety logic 26 has logic circuitry, which can be in the form of discrete IC circuits, a microcontroller, and / or an FPGA, for example. The logic circuit is configured to compare the switching states of the safety contacts 8B, 9B and to block the supply of current through the IGTB transistor 25 in case one of the contacts of the safety relay 8B, 9B remains in the state closed while than the other 8B, 89B changes from closed state to open state and then back to closed state. This particular logic allows detecting if one of the brake opening switches 8A, 8B; 9A, 9B has failed and is stuck in closed position. Furthermore, in that case the opening of the brakes 7 is prevented to guarantee the safety of the elevator.

The brake control unit 1 also comprises a speed supervision logic 28 in the form of a microcontroller. The function of the speed monitoring logic 28 is to reduce the speed of the elevator car to prevent the safety equipment from tripping during the rescue operation. The speed supervision logic microcontroller 28 is connected to the input terminal 29. The input terminal 29 is connected to a motion sensor that measures the movement of the elevator car 31. The motion sensor is a motion sensor. acceleration 30 mounted on the elevator car 31. The acceleration sensor 30 measures the acceleration of the elevator car 31. The microcontroller integrates the signal from the acceleration sensor 30 to obtain the speed of the elevator car.

An output of the microcontroller of the speed supervision logic 28 is coupled to an input of the modulator 27, such that the microcontroller can selectively enable or prevent the supply of current to the magnetizing coils 6 through the IGBT transistor 25. In some In embodiments, the microcontroller compares the speed of the elevator car with a threshold value and interrupts the supply of current to the magnetizing coils 6 when the speed of the elevator car exceeds the threshold value. When the current supply to the magnetizing coils 6 is interrupted, the brakes of the elevator machine 7 are applied to slow down the movement of the elevator car.

In addition, the speed monitoring logic 28 is configured to detect acceleration sensor malfunction, when the speed of the integrated elevator car remains at zero (within an accepted tolerance) at least for a predetermined period of time after that the contacts of the safety relay 8B, 9B have closed and current is supplied through the IGTB transistor 25 to the magnetizing coils 6. This means that a malfunction is detected if no movement signal is received after the brakes 7 are released and the elevator car begins to move due to gravity. When the fault is detected, the speed supervision logic 28 interrupts the supply of current to the magnetizing coil 6 and the brakes 7 are applied.

Current is supplied from the normal mode brake control device 17 to the magnetizing coils 6 through the brake control unit 1. In rescue mode, the normal mode brake control device 17 is isolated from the magnetization coils 6 and the brake control unit 1 is connected to the magnetization coils 6 in such a way that the brake control unit 1 can supply current to the magnetization coils 6 without any interference from the brake control device in normal mode 17. Consequently, in normal mode, the brake control unit 1 is isolated from the magnetizing coils 6 and the normal mode brake control device 17 is connected to the magnetizing coils 6 in such a way that the normal mode brake control device 17 can supply current to the magnetizing coils 6 without any interference from the brake control unit 1. This isolation function it is implemented in the brake control unit 1 as revealed below.

The power supply cables of the brake control unit 1 in normal mode are connected to the step terminals 5 of the brake control unit 1. The power supply cables of the magnetizing coils 6 are also connected to the output terminals 4 of the brake control unit 1. The brake control unit 1 comprises a switch with first inputs 18A, second inputs 18B and outputs 18C. The first inputs 18A are coupled to the pass-through terminals 5 and the second inputs 18B are coupled to the rescue time current supply, eg, to the current path of the input terminals 2A, 2B. In the embodiment of Figure 2 the second inputs 18B are coupled to the emitter of the IGBT transistor 25. The outputs 18C of the switch are coupled to the output terminals 4.

The control pole 18D of the disconnect switch is coupled by a control signal wire 11C to the manual mode selection switch 15A on the remote control panel 12.

When the mode selection switch 15A is set to normal operation state (open state), current is supplied from the normal mode brake control device 17 through the first inputs 18A of the switch, and further through the output terminals 4 to the magnetizing coils 6. At the same time, the second inputs 18B remain open, thus isolating the magnetizing coils 6 from the IGTB transistor 25.

When the mode selection switch 15A is put into the rescue operation state (closed state), current is supplied from the input terminals 2A, 2B through the IGTB transistor 25 and the second inputs 18B further through the terminals output 4 to the magnetizing coils 6. At the same time, the first inputs 18A remain open, isolating the magnetizing coils 6 from the normal mode brake control device 17.

One of the contacts of the mode selection switch 15B is in the elevator safety chain 19. In the disclosure the term "elevator safety chain" has to be understood broadly, including the traditional series connection circuits of the contacts. elevator safety, as well as modern Electronic security devices programmed enabled in the new elevator security codes. Switch contact 15B closes during normal elevator operation and opens in rescue mode. The opening of the switch contact 15B means that the safety chain of the elevator 19 is interrupted. When interrupted, the safety chain 19 blocks the normal operation of the elevator, thus improving the safety of the rescue operation.

The rescue apparatus of Figure 1 also comprises the dynamic braking switches 20A, 20B. The dynamic braking switches 20A, 20B are used to slow down the rotation of the lift machine 23 during the rescue operation, to stabilize the movement of the elevator car during the rescue operation. The connection principle of the dynamic braking switches 20A, 20B is shown in Fig. 4. When closed, the dynamic braking switches generate a braking current from the electromotive force of the permanent magnet motor 22 of the lifting machine. 2. 3.

The terminals of the dynamic braking switches 20A, 20B are coupled to the stator winding 21 of the permanent magnet motor 22. In the embodiment of Figure 4, the dynamic braking switches 20A, 20B are normally closed (NC) contacts of a contactor or a relay. This means that dynamic braking is always possible even when no control voltage is available, for example during a power failure. On the other hand, instead of mechanical switches, solid state switches can also be used (such as IGBT transistors, MOSFET transistors, gallium nitride transistors, silicon carbide transistors, etc.). The control coil 20C of the dynamic braking contactor is coupled to the elevator safety chain 19. The current of the control coil 20C is interrupted to allow dynamic braking when the switch contact 15B is opened (for example, during rescue operation).

The invention is described above with the aid of exemplary embodiments. It is obvious to a person skilled in the art that the invention is not limited to the embodiments described above and that many other applications are possible within the scope of the claims.

Claims (14)

1. A rescue apparatus for an elevator, the rescue apparatus comprising: a brake control unit (1) having input terminals (2A, 2B) for connection to a power supply (3A, 3B), output terminals (4) for connection to a magnetizing coil (6) of an electromagnetic brake (7), and two independently controllable brake release switches (8A, 8B; 9A, 9B) each associated with at least one of the input terminals (2A, 2B) and adapted, in the open state, to prevent the supply of current from the source power supply (3A, 3B) to the magnetizing coil (6) and, in the closed state, to allow the supply of current from the power source (3A, 3B) to the magnetizing coil (6); a control cable (10) comprising a plurality of control signal cables (11A, 11B, 11C); Y a remote control panel (12) to operate the two brake release switches (8A, 8B; 9A, 9B), the remote control panel (12) being coupled via the control cable (10) to the control unit control of the brake (1), the remote control panel (12) comprising two manually actuated switches (13A, 13B), one of the actuation switches (13A, 13B) being coupled via a first control signal cable (11A, 11B) to a control post (8C, 9C) of the first brake release switch (8A, 8B); 9A, 9B) and the other of the actuation switches (13A, 13B) being coupled through a second control signal cable (11A, 11B) to a control post (8C, 9C) of the second opening switch of the brake (8A, 8B; 9A, 9B). 2. The rescue device according to claim 1, wherein the power supply is a backup power source (3B). 3. The rescue device according to claim 2, wherein the power supply is a power supply DC backup (3B), and wherein the control unit the brake (1) comprises a DC / DC (16) to supply electricity from the backup power source (3B) to the magnetizing coil (6). 4. The rescue device according to any of the preceding claims, wherein the power supply is (3A) grid. 5. The rescue device according to any of the preceding claims, wherein the rescue device comprises switches controllable dynamic braking (20A, 20B) having terminals for coupling to a stator winding (21) of a motor magnets permanent (22), the dynamic braking switches (20A, 20B) being adapted to generate, in the closed state, a braking current from the electromotive force of the permanent magnet motor (22). 6. The rescue device according to any of the preceding claims, wherein the control unit the brake (1) comprises a solid state switch (25) associated with the output terminals (4) to prevent or selectively permitting supply of electricity to the magnetizing coil (6). 7. The rescue device according to claim 6, wherein the control unit comprises a brake modulator (27) coupled to the control pole of the solid state switch (25), and the modulator (27) is configured to adjust the voltage of the output terminals by modulating the solid state switch (25). 8. The rescue device according to claim 6 or 7, wherein the control unit the brake (1) comprises a logic speed supervision (28) having an inlet (29) to receive movement data the elevator car and an output coupled to the control pole of the solid state switch (25). 9. The rescue device according to claim 8, wherein the monitoring logic speed (28) is coupled to the status indicator switch (14) for receiving information of the switching state of the switches opening brake ( 8A, 8B; 9A, 9B). 10. The rescue device according to claim 8 or 9, wherein the monitoring logic speed (28) is configured - to determine the speed of the elevator car from the motion data, and - to compare the speed of the elevator car with a threshold value, and - to interrupt the current supply to the magnetizing coil (6) if the speed of the elevator car exceeds the threshold value. 11. The rescue device according to claim 9 or 10, wherein the monitoring logic speed (28) is configured - to interrupt the supply of current to the magnetizing coil (6) if the speed of the elevator car remains within a tolerance given at zero for a predetermined period of time after the brake opening switches (8A, 8B; 9A, 9B) have entered the closed state. 12. The apparatus according rescue any of claims 8 to 11, wherein the motion data of the elevator cabin are measurement data of an acceleration sensor (30) mounted on an elevator car (31). 13. An elevator, comprising an elevator car (31) and a lifting machine (23) configured to drive the elevator car in the elevator shaft (33) between the landings (34) according to passenger service requests of the elevator, the elevator machine (23) including one or more electromagnetic brakes (7), wherein the elevator comprises a rescue apparatus according to any of the preceding claims. 14. A modification kit comprising a rescue device according to any of claims 1 to 12, rescue apparatus that is suitable for installation in an elevator according to claim 13.